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Evidence for Ordered Magnetic Fields in the Quasar Environment

P. S. Udomprasert·G. B. Taylor·T. J. Pearson·D. H. Roberts
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Abstract

At a distance of 20 pc from the purported supermassive black hole powering quasars, temperatures and densities are inferred from optical observations to be ~10**4 K and ~10**4 cm**-3. Here we present Very Long Baseline Interferometry radio observations revealing organized magnetic fields on the parsec scale in the hot plasma surrounding the quasar OQ172 (1442+101). These magnetic fields rotate the plane of polarization of the radio emission coming from the core and inner jet of the quasar. The derived rotation measure (RM) is 40,000 rad m**-2 in the rest frame of the quasar. Only 10 mas (a projected distance of 68 pc) from the nucleus the jet absolute values of RM fall to less than 100 rad m**-2.

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P. S. Udomprasert, G. B. Taylor, T. J. Pearson, D. H. Roberts. 1997-04-12. Evidence for Ordered Magnetic Fields in the Quasar Environment. https://doi.org/10.1086/310725

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